BDUMP trace directory is where debugging trace files for the background processes is stored. these may not be useful for daily jobs but if at times there is a crash , of during an updation in oracle SR they are needed to debug any issues.

You can check it from:

sqlplus "/ as sysdba"
show parameter dump

You can pruge them periodically but as far as i know , you cannot stop the generation of this.

Instead of stopping it, you can restrict the size of trace files so that it will not occupy all the space.

You can set parameter MAX_DUMP_FILE_SIZE for specifying the size.

This parameter specifies the maximum size for dump files such as trace files.
The unit of this parameter is measured in physical operating system blocks unless it has a suffix M or K,
in which case the unit is Megabyte and Kilobyte, respectively.